Motion-based music applications exploit the connection between body movements and musical concepts to allow users to practice high-level structured elements (e.g., tonal harmony) in a simple and effective way. We propose a framework for the design and the assessment of motion-based music applications by involving outcomes from various disciplines, such as the cognitive sciences and human–computer interaction. The framework has been applied to a working system, the Harmonic Walk, which is an interactive space application based on motion-tracking technologies. The application integrates both digital and physical information by reacting to a user’s movements within a designated 3 x 4 m floor, where six musical chords have been arranged according to a determined spatial positioning. Human choreographies from the user’s coordinated movements to musically structured events are analyzed in order to determine their relationships and to discuss related design issues.